Simultaneous hot desulfurization and improved filtration in coal utilization processes

The primary objective of this Phase 1 SBIR effort was to investigate the relative effectiveness which various waste metal oxides might have in the removal of sulfur from sulfur dioxide (SO{sub 2}) and hydrogen sulfide (H{sub 2}S) gas streams, under controlled laboratory conditions. A number of waste metal oxides were tested both individually and in combination, to assess their capacity for sulfur capture in sulfur laden oxidizing and reducing atmospheres. Additionally, inert materials such as silica sand, as well as more traditional sorbents, such as dolomite and limestone, were tested to serve as reference data. The Phase 1 effort also explored the overall domestic availability of the best performing waste metal oxide sorbents, taking into account their geographic distributions, intrinsic value, etc. to provide the groundwork for a low cost, highly effective sulfur sorbent which can be quickly implemented on a commercial scale for such processes as IGCC and PFBC. Finally, in that all of the sorbent samples tested were of an identical, carefully selected particle size, the data collected serves as the basis for a proposed Phase 2 effort, which will further utilize the waste metal sorbents as a means of increasing the permeability of the dust collected on downstream particulate control devices, such as ceramic filters. The Phase 1 SBIR effort reported herein showed that significant sulfur removal capacities can be obtained using classified, spent metal oxides. Among the spent metal oxides tested in Phase 1 which exhibited a strong affinity for sulfur capture in oxidizing and reducing atmospheres were the waste oxides of tin, zinc, and iron, some of which had significantly higher capacity than a mixture of dolomite and limestone